Fix yaml formatting error with multiple annotations (#9104)

When using multiple values for the `serviceAccount.annotations` values, the first line ends up indented 2 further than the following lines, resulting in a invalid yaml

Author: mklauber

charts/ingress-nginx/templates/controller-serviceaccount.yaml

@@ -12,7 +12,7 @@ metadata:
   namespace: {{ .Release.Namespace }}
   {{- if .Values.serviceAccount.annotations }}
   annotations:
-  {{ toYaml .Values.serviceAccount.annotations | indent 4 }}
+  {{- toYaml .Values.serviceAccount.annotations | indent 4 }}
   {{- end }}
 automountServiceAccountToken: {{ .Values.serviceAccount.automountServiceAccountToken }}
 {{- end }}